Nut and nut and screw fastened installation



gamma g-. 23, 1932. A. w. KHMBELL NUT'AND NUT AND SCREW FASTENEDINSTALLATION Filed Aug. 1. 19m

Patented Aug. 23, 1932 UNITED STATES PATENT; orricE I .ARTHUR W.KIMBELL, OF NEWTON CENTER, MASSACHUSETTS, ASSIGNOR TO UNITED- CARRFASTENER GORPORATION, OF CAMBRIDGE,

TION or mnssncnusm'rs mm mm mm AND scnnw MASSACHUSETTS, A CORPORA-FASTENED INSTALLATION Original application filled April 27, 1931, SerialNo. 533,080. Divided and this application filed August My invention aimsto provide improvements in nuts and nut and screw fastened installationsand also the method of making the nuts.

This application is a divisional of my a plication Serial No. $3,080,filed April 2%, 1931.

In the drawing whichillustrates a preferred embodiment of my inventionFigure 1 is a section through a portion of an installation showing myinvention in use;

Fig. 2 is an end elevation of my improved nut member; and

Fig. 3 is an enlarged cross-sectional view through my improved nutmember, a portion of an attaching screw being shown in elevation.

Referring to my invention as illustrated by the annexed drawing there isshown an improved nut member for nut and screw fastened installations.The nut illustrated is pressed from a single piece of sheet metal andhas a base flange 1 from which extends a hollow shank 2. Any suitablemeans may" be provided for preventing rotation of the nut when attachedto a part of an installation, but I have shown a number of coneshapedprojections 3 for this purpose. The cone-shaped projections 3 arepressed from the material of the base and spaced inwardly from theperiphery thereof so that the nut may be made from a minimum sizedblank.

Hcretofore nut members of the general type referred to above have beenused in which the shanks were threaded internally with an ordinaryV-type thread for coopera tion with the threaded shank of an attachingscrew. I have found that in nut members wherein the shank is ofsubstantial length and drawn from the material of the base the ordinaryV-type thread extends so nearly entirely through the wall of the shankthat it is weakened to such an extent'that the shank breaks when asubstantial axial stress is exerted thereupon. Since the thickness ofthe wall of the shank cannot be increased for several obvious reasons, Ipropose to strengthen the shank by decreasing the distance that thethread is'cut into the shank, as shown in Fig. 3. I have found that Tcan Serial No. 554,437.

with a standard V-shaped thread on the shank 5 of the attaching screw 6.If desirabl-e, the shank 5 of the screw maybe provided with a threadwhich is the same shape as the thread 4 formed in the shank 2 of thenut.

As a result of my invention T have provided a nut which is adapted tocooperate with a standard screw but which has a shank threaded asdescribed above so that there is suficient unthreaded material betweenthe outer face of the shank and the bottom of the thread 4 to preventfracture or complete breakage of the shank 2 when substantial. stressesare exerted upon the shank through the'screw. While there is not as muchcontact between the surfaces of the thread 4 of the shankof the nut andthe surfaces of the thread of the shank of the screw (Fig. 3) as therewould be by providing a full V-shaped thread in the shank of the nut,nevertheless, I have found'that the length of the shank 2 of the nut, asillustrated in the drawing, is more than sufficient to provide anintercngagement of the threads sufficient to withstand any normal axialstresses which would tend to strip the threads from either the shank ofthe screw or the shank of the nut. I have, therefore, increased thestrength of the shank of the nut without affecting the practicalinterlocking engag ment between the thread of the shank of the nut andthe 2 reraeee have shown a portion of this type of installation whichincludes the sheet metal door 7, the Wooden lock board 8 secured withinthe door 7 and a part 9, which may be the remote control handle device,the window regulator,

' or other part attached to the lock board 8.

In this particular installation, the shank 2 of the nut extends into abore 10 in the board 8 and the screw 6 extends through an aperture 11 inthe part 9 and engages with the shank of the nut. As the nut and screware threaded together, the projections 3 on the base of the nut areforced into the wooden board 8, thereby preventing rotation of the nut.If the board 8 is of soft wood the tightening of the screw willcountersink the base 1 into the wood, as shown in Fig. 1, so

that when the board 8 is placed in the door 7 there need be little or nospace between the door and the lock board.

From an inspection of Fig. 3 it is apparent I that the pitch of thethread 4 of the shank 2 of the nut is at least twice as great as theheight of the thread. This provides strength against axial stressestending'to strip the thread. It is also apparent that the fiat ton ofthe thread 4 is about equal to the height of the thread This gives astrong thread and aids against stripp ng. I do not wish to be limited tothe dimensions shown and described because they may be varied to somedegree depending upon the use of the nut and the stresses to which itmay be subiected. The proportions given for the thread 4 and thethickness of the unthreaded portion of the wall of the shank 2 have beentried and found practical and nuts of this construction are incommercial use and are proving very satisfactory.

While I have illustrated and described a preferred embodiment of myinvention, I do not wish to be limited thereby because the scope ofmyinvention is best defined by the following claims. 7

Claims:

1. A sheet metal nut having a base, a hol-' low relatively thin walledshank extending from said base and a thread formedinterna" v of saidshank, said thread having a substantially wide flat face throughout itslength at the inner surface of said shank and being otherwise of theconventional high pltched V-shaped type out only part wayintothethickness of the wall of the shank, thereby leavin an unthreadedthickness of the wall whic is greater than would be provided by cuttingthe thread in the conventional manner.

2. A sheet metal nut having a base, a -hollow shank drawn from the metalof said'base and a thread formed internally of said shank the internalportion of said thread being 0 the sharp ll-type but cut into the wallonly to such a depth as to provide a blunt top at the inner face of theshank, the width of said top being about equal to the height of thethread from top to bottom.

In testimony whereof, I have signed my name to this specification.

ARTHUR W. KI Y- no i

